As reports come in on the military coup in Turkey late Friday, US and NATO leaders have had little to say on the situation. Turkey and its President Tayyip Erdogan are major allies of the United States.
The Turkish military has backed up the United States and NATO forces in the wars in Iraq and Afghanistan.
Turkey is among 28 groups part of the NATO alliance.
NATO hasn't responded immediately to a request for comment on how alliance operations or Turkey's status might be affected after the military said it seized control of the country.
Independent observers noted that the 1949 treaty that created the U.S. alliance has no mechanism for suspending members, unlike the United Nations, the European Union or the Organization of American States.
Nothing in NATO's founding 1949 Washington Treaty says anything about intervening in the internal or political affairs of an alliance member, and Turkey kept its NATO membership following past military coups.
The treaty's key clause, Article 5, stipulates that NATO member states agree that "an armed attack against one or more of them in Europe or North America shall be considered an attack against them all," but that language has taken to apply to an external enemy.
U.S. Secretary of State John Kerry says he hopes for stability and continuity in Turkey following reports that an attempted military coup is under way in the NATO member state.
Kerry, in Moscow for talks on Syria with Russian officials Friday, said that the US will back the "democratically-elected civilian government and democratic institution."
Earlier, troop movements and low-flying military aircraft were reported in Istanbul and the capital, Ankara, and Turkey's prime minister said some elements of the military were attempting a coup. Turkey's military said it had seized control.